Geological map of north central Texas, above; map of central Texas, below, from Petermann's Geographishce Mittheilungen.
The upper map reports the work of Dr.'s Loew and A.R. Roessler, including Dallas in the east. The lower map is a detailed general map showing a large portion of Texas, including forts, roads, railroads and other detalls.
Petermann's Geographical Bulletin compiled many of the great cartographic works of exploration during this period. The set is increasingly scarce and the individual maps appear only infrequently on the market.